* {
    user-select: none;
    -moz-user-select: none;
}

@media print {
    body {
        display: none;
    }
}

body {
    display: flex;
    flex-direction: column;
    align-content: center;
    justify-content: center;
    width: 100vw;
    height: 100vh;
    margin: 0;
    padding: 0;
}

iframe {
    width: 500px;
    height: 100vh;
    max-width: 500px;
}